1. Field of the Invention
This invention relates, generally, to locking devices and more particularly to an interlocking means for preventing the simultaneous throwing of at least two switch actuators.
2. Description of the Prior Art
Power distribution centers often require cooperation between switch actuators.
Typically, the actuators operate to toggle power between alternate sources and are situated adjacently for convenience. Thus, when one switch is thrown to an xe2x80x9conxe2x80x9d position the complementary switch is in an xe2x80x9coffxe2x80x9d position and vice versa. However, the convenience of having switches in close proximity leads to the vulnerability of the switches being accidentally thrown simultaneously. Thus, a variety of interlocking devices have been developed to prevent the simultaneous throwing of switches to an xe2x80x9conxe2x80x9d position.
Continuing efforts are being made to improve interlocking devices. By way of example, note U.S. Pat. No. 5,902,974 to Fogle et al. that describes a slide bar interlock designed specifically for use with adjacently positioned circuit breakers having dissimilar actuating means. Similarly, U.S. Pat. No. 4,286,242 to Mrenna et al. describes plungers that engage the internal operating mechanisms of circuit breakers. Notwithstanding the existence of such prior art interlocking devices, there is a need for an improved and more efficient switch actuator interlock.
In summary, the needed improvements include an interlocking device that is easy to operate which is also durable and relatively failsafe.
However, in view of the prior art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in the pertinent art how the identified needs could be fulfilled.
The long-standing but heretofore unfulfilled need for an interlocking device for adjacent circuit breakers that is easy to operate, relatively failsafe, which prevents simultaneous throwing of at least two switch actuators, is now provided in the form of a new, useful and non-obvious device.
The interlocking device includes a pair of switch actuators mounted on a support surface in lateral relation to one another. Each switch actuator of the pair of switch actuators has a down position and an up position. An elongate locking bar is provided with two laterally spaced apart switch actuator-receiving recesses formed therein. The elongate locking bar is slideably mounted relative to the support surface for lateral displacement in closely spaced relation to said pair of switch actuators. The elongate locking bar has a first position where a first switch actuator receiving recess is in alignment with a first switch actuator so that said first switch actuator can be thrown. A second switch actuator recess is misaligned with a second switch actuator when said first switch actuator recess is in alignment with the first switch actuator. The elongate locking bar has a second position where the second switch actuator receiving recess is in alignment with the second switch actuator so that the second switch actuator can be thrown. The first switch actuator recess is misaligned with the first switch actuator when the second switch actuator recess is in alignment with the second switch actuator. The elongate locking bar prevents simultaneous throwing of the pair of switches.
An important object of the present invention is to provide an improved interlocking device, for use with circuit breakers and the like that prevents the simultaneous throwing of at least two switch actuators.
Another object is to provide an interlocking device that can be operated without undue effort so that the locking device provides a relatively failsafe device that protects associated equipment and persons from potential harm.
Another object is to provide a locking device suitable for different equipment without modification and which is durable and not susceptible to breakage.
These and other important objects, advantages, and features of the invention will become clear as this description proceeds.
It is to be understood that both the foregoing general description and the following detailed description are explanatory and are not restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute part of the specification, illustrate embodiments of the present invention and together with the general description, serve to explain principles of the present invention.
The invention accordingly comprises the features of construction, combination of elements, and arrangement of parts that will be exemplified in the description set forth hereinafter and the scope of the invention will be indicated in the claims.